Of all the great appetizers to be appetized in the vicinity, the mushroom strudel at Sidney Street Café floats in a high stratum. A flaky phyllo crust encloses a melange of porcini, shiitake and oyster mushrooms; Gouda and Swiss cheeses; shallots reduced with pinot noir; and herbs and spices. The strudel, which looks like little blintzes, is coated with a sauce of more wine, herbs and spices. Though the appetizer is vegetarian, the reduced wines and other ingredients give it a rich taste that suggests beef stock. Sometimes a chef hits the right combination and hits it hard. Noted Sidney Street chef Annie Dill's take on this dish sets the body's pleasure chemicals in motion. You may want to order a second round.